Lent is the 40-day period prior to Easter, and it is characterized by penance via prayer and fasting. In the Western church it begins on Ash Wednesday and lasts until Easter. It is believed that the tradition began in the Apostolic era, and it was observed by all the ancient churches. However, there was a time that philosophies began to differ and so some churches stopped observing Lent.
The abolition of Lent came in the 16th century when the Anabaptists rejected all the Christian holy days. They believed that these holy days were created by the Romans. Their influence is prominent in Amish, Mennonite, Baptist, and Puritan churches. Anabaptist influences were so strong that Puritans even made Christmas illegal in Massachusetts at one time. By the 19th century many religious groups in the U.S. no longer observed Lent.
Some late 19th Century experts, though, discovered documentations that contradict the Anabaptist belief that the Holy Days were a Roman innovation, as some of them show that Rome was one of the last places to observe holy days. The 1st century Didach, the 3rd century Apostolic Constitutions, and the 4th century diaries of Egeria provide some foundation for the practice of the holy days. Yet the discovery of these documents came 300 hundred years after many Christian groups had abolished certain holy days.
Due to these findings and some Christians' desire for greater tradition, some churches are now bringing back some of the traditions that had been lost over the centuries. Still, not all churches observe holy days like Ash Wednesday or Lent, which is why some Christian teens participate in different traditions during the Easter holidays.